1. Field of the Invention
This invention relates to the field of robotic installations and devices that have a high precision and a very good safety of use, allowing their implementation in a medical context.
2. Description of the Related Art
This invention more particularly has as its object a robotized installation for the positioning and the movement of a component or instrument, a transcranial magnetic stimulation device that comprises such a robotized installation and a transcranial magnetic stimulation process that implements the above-mentioned device.
In numerous procedures for treating patients or for medical imagery, it is necessary to carry out precise and repeated positionings and movements of components or instruments if necessary over often consistent lengths of time (several tens of minutes).
These experiments are tedious and exhausting for the operator, even when they are assisted mechanically to facilitate the execution thereof.
In addition, the operator should necessarily be a specialized individual, i.e., in general a surgeon, a neurologist, a radiologist or an analogous specialist, depending on the components in question and the type of treatment or investigation to be carried out.
In addition, even an experienced operator, optionally able to exploit a visual return provided by a navigation system, cannot ensure a positioning or a movement in optimum agreement with previously calculated data nor a fortiori the identical repetition of a given procedure, requiring several similar successive applications to be effective.
Finally, according to the type of treatment or investigation to be carried out, the operator that manually handles the component or the instrument is exposed to a harmful radiation.
These different factors explain the demand of practitioners for the implementation of robotized installations.
Several problems disclosed above are posed in particular relative to the transcranial magnetic stimulation that is designed to issue electrical stimulation to the cerebral cortex.
The effectiveness of this process was demonstrated in the case of depression, and studies are currently being conducted for pathologies other than post-traumatic anxiety, obsessive-compulsive disorders, schizophrenia, and even for certain types of epileptic disorders.
However, a significant variability of the effectiveness according to the patient that is primarily due to the difficulty of the handling of the kind of stimulation system as it currently exists and that makes it almost impossible to reproduce the same procedure identically has been observed.
Actually, during the implementation of the current procedures, as soon as the target zone of the cortex has been defined by the functional use of MRI images, the probe that integrates the magnetic stimulation coil is to be moved manually on the patient's head by the neurologist in order to follow the precise path in space.
However, even when a visual follow-up is provided to the neurologist by a navigation system for the purpose of facilitating the positioning of the coil, it was noted that in practice, it was impossible to obtain a precise movement of the probe.
In addition, such a manual treatment is extremely detrimental in terms of the price of the procedure, taking into account the necessary qualification of the operator and the significant duration of each treatment sequence.
Various implementations of robotized devices for medical use, designed to position and/or to move a component or an instrument relative to a patient, are already known.
Nevertheless, these existing systems, often derived from industrial robotic devices, are not suitable for moving a tool or an instrument at the surface of a patient, do not ensure adequate precision in terms of their movements and/or exhibit an inadequate level of safety of use for a medical application.
Furthermore, by the document “Psychiatry's Shocking New Tools” of Samuel K. Moore, IEEE Spectrum, March 2006, a theoretical representation of a transcranial magnetic stimulation device that comprises an articulated structure that supports the application probe of a pulsed magnetic field is known.
This structure, automatically piloted or controlled remotely by an operator, comprises a telescopic bracket, at the end of which is suspended, by means of a rotoidal connection, an articulated sub-assembly that carries the probe.
The sub-assembly itself comprises a moving circular rail, one of whose ends is integral, by means of a rotoidal connection, with a slide rail, on which the probe is mounted in a sliding manner.
Thus, the combination of these different articulated connections provides only five degrees of freedom and thereby only points of the upper part of the cranial cap can be reached by the probe of this device according to this document.
In addition, it seems that this structure does not make it possible to carry out a scanning from front to rear on the patient's head, and it would be necessary to complete said structure by two additional degrees of mobility in translation in a horizontal plane to be able to scan the entire upper surface of the skull.
Furthermore, no mechanism for controlling the orientation of the transcranial magnetic stimulation probe, around a contact point, is provided.
Finally, it is noted that the management of the contact effort, if it is optionally provided (the IEE Spectrum document does not mention it), would be difficult to implement taking into consideration the architecture of the structure. It is also noted that it is not possible to move the probe along a single axis in case of incident, such as a power failure, without running the risk of interfering with the patient's head, and that the multiplication of the cantilevers has a negative effect on the rigidity of the structure and the precision of the movements of the probe.